About tne nations: as you know, the number of units is limited, so in the last version of MWM I was pushed to devide the european unitpack to provide room for new units. There are two European unitpacks now.
1) Donbass and the Caucasus - USA, Russia, Germany, UK + Ukrain, Georgia, Donetzk/Lugansk people's republic
2) Koenigsberg - USA, Russia, Germany, UK + France, Belorussia, Poland
Both are available in summer and late autumn setting.
And, of course, there is
3) Middle East - Syria, Israel, Turkey, Russia, USA, Iran, Syrian opposition